Banca de DEFESA: RODRIGO ALBERT BARACHO RUEGG

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : RODRIGO ALBERT BARACHO RUEGG
DATE: 27/03/2026
TIME: 14:00
LOCAL: REMOTA
TITLE:

EXPLORING THE APPLICABILITY OF A-MODE ULTRASONOGRAPHY IN THE CLINICAL CONTEXT OF MUSCLE MASS ASSESSMENT

KEY WORDS:

Body composition; cancer; muscle health; survival; ultrasonography; magnetic resonance imaging.

PAGES: 66
BIG AREA: Ciências da Saúde
AREA: Nutrição
SUMMARY:

Skeletal muscle mass assessment is fundamental for the clinical management of various conditions, especially cancer, where protein depletion is associated with poorer outcomes. Although advanced imaging methods are the gold standard, the search for bedside tools, such as Amplitude-mode (A-mode) ultrasound, has become essential for hospital practice. This thesis is composed of products derived from two studies that investigated the applicability of this technology. The first study aimed to evaluate the technical validity of A-mode ultrasound compared to Magnetic Resonance Imaging (MRI) in 95 healthy young adults (60% female; 29 ± 6 years). Biceps and quadriceps muscle thicknesses were measured via ultrasound, and skeletal muscle area (SMA) was assessed by MRI at the third lumbar vertebra level. The results demonstrated that biceps muscle thickness (BMT) showed a strong correlation with MRI-derived SMA (r = 0.82; R² = 0.68; p < 0.001), significantly outperforming thigh measurements. These findings support the use of A-mode ultrasound as a viable, low-cost surrogate for global muscle mass estimates. The second study applied this tool in an oncological context, investigating the association between muscle thickness and adverse clinical outcomes in 358 patients (53.6% female; 50.4% with gastrointestinal tumors; 42.5% with TNM stage IV). Muscle thickness was measured at the biceps (BMT) and the thigh (TMT). The findings showed that only BMT was an independent predictor of 30-day and 6-month mortality. Each one-millimeter increase in BMT reduced the risk of 30-day mortality by 9% (95% CI: 0.85–0.96) and 6-month mortality by 6% (95% CI: 0.91–0.98), while TMT showed no significant predictive value for survival or prolonged hospitalization.The findings of this thesis reinforce that A-mode ultrasound is a technically validated tool for muscle assessment, with biceps thickness serving as a robust indicator of survival in cancer. This technology stands out as a valuable bedside strategy for early risk identification, allowing for the implementation of timely interventions and the optimization of care for cancer patients in resource-limited settings.

COMMITTEE MEMBERS:
Externa à Instituição - LARA VILAR FERNANDES - UNICAMP
Externo à Instituição - ALEXANDRE COELHO SERQUIZ - UFPB
Presidente - 1879430 - ANA PAULA TRUSSARDI FAYH
Externa ao Programa - 2306763 - KARINE CAVALCANTI MAURICIO DE SENA EVANGELISTA - nullInterna - ***.476.444-** - LUCIA DE FATIMA CAMPOS PEDROSA - UFRN